The invention relates to silicon oxide particles having small particle diameters. The method further relates to method of producing the silicon oxide particles based on laser pyrolysis and polishing compositions including the silicon oxide particles.
Technological advances have increased the demand for improved material processing with strict tolerances on processing parameters. In particular, smooth surfaces are required in a variety of applications in electronics, tool production and many other industries. The substrates requiring polishing can involve hard materials such as ceramics, glass and metal. As miniaturization continues even further, even more precise polishing will be required. Current submicron technology requires polishing accuracy on a nanometer scale. Precise polishing technology can employ mechanochemical polishing involving a polishing composition that acts by way of a chemical interaction of the substrate with the polishing agents as well as an abrasive effective for mechanical smoothing of the surface.
The invention features a collection of particles comprising amorphous silicon oxide having primary particles with an average diameter from about 5 nm to about 100 nm. The collection of silicon oxide particles effectively include no particles having a diameter greater than about four times the average diameter. In another aspect, the invention features a polishing composition including a dispersion of silicon oxide particles having an average primary particle diameter from about 5 nm to about 100 nm. The collection of silicon oxide particles in the dispersion effective includes no primary particles having a diameter greater than about four times the average diameter.
In another aspect, the invention features a method for processing a collection of silicon oxide particles having an average diameter from about 5 nm to about 1000 nm. The method includes heating the collection of particles comprising silicon oxide at a temperature from about 400xc2x0 C. to about 800xc2x0 C. In another aspect, the invention features a collection of particles comprising silicon oxide, the collection of particles having an average diameter from about 5 nm to about 1000 nm, the collection of particles being produced by forming particles comprising silicon oxide by laser pyrolysis and heating the particles produced by laser pyrolysis under an oxidizing atmosphere at a temperature from about 400xc2x0 C. to about 800xc2x0 C. for a sufficient period of time to decolorize the particles.